I've been using the Tornado T now for about 2 weeks and I love the vap and the amount of time between refills. However, I find that it leaks.. all the way through almost. Not all the time.. sometimes with brand new cartridges and sometimes after I've refilled one a few times. Often it leaks out the pipe, which sucks because it's a mouthful of liquid.. sometimes it's at all the seams (between atomizer/cartridge). Is there a difference between refill cartridges and just refilling a pre-packaged cartridge? Trying to figure out if it's operator issue or something with my mechanism? Thoughts?